Make sure that %ServerName; is online and remotely accessible from the DPM server. 2) If a firewall is enabled on %ServerName;, ...

1) Make sure that %ServerName; is online and remotely accessible from the DPM server.
2) If a firewall is enabled on %ServerName;, make sure that it is not blocking requests from the DPM server.
3) If you are using backup LAN, make sure that the backup LAN settings are valid.